Improvement in steam engines



i JHN SBARDEN, OF PROVIDENCE, RHODE ISLAND.`- Laim Patent No. 61,916,@zaad February 12, 1867.

IMPRUVEMENT vIN STEAM ENGINES.

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TO ALL PERSONS` T0 WHOM THESE PRESENTS SHALL COME:

Be it known that I, JOHN S. BAnDEN, of the Vcity and county ofProvidence, and State of `Rhode Island, V

have invented a new'and useful or improved Steam Engine.; and I dohereby declare the same to be fully described in the followingspecification, and represented in the accompanying drawing, whichdenotesa lcngi` tndinal section applied to a double-acting force-pump.

- In this engine there are'two heads to the piston, thelexhaust steam inescaping being caused to pass 1aterally through the cylinder, andbetween the said two connected heads applied to the piston-head.

In the drawings, A denotes the cylinder, provided with steam passages orports, a b, leading from the two ends of its bore to and through avalve-seat, c, of a valve chest, B, applied to one side of `thecylinder.. Between the two ports a b is an exhaust port or passage, d,which leads out of the valve-seat and laterally through opposite sidesof the cylinder,v in manner as represented in the drawing, and to anescape hole, d. Within the cylinder is a double-headed piston, that is,one provided with two heads to its rod, such two heads being 'shown` atC D, and the rod at The heads are arranged within the cylinder in manneras exhibited, and are connected by a rod, F, provided with a long slot,e,`made vertically through and longitudinally in The longer arm of thelever G, which is arranged within the cylinder and the exhaust passaged, and has its fulerum atf, as shown inthe drawing, extends into theslot ve. The shorter arm of the said lever enters an angular recess, g,made in a movable plate, 7L, which'constitutes part of a slide valve H,placed on the seat c, and within the steam chest B. The plate hisrectangular, and slides vertically within a rectangular frame, z', 4andup against an elastic plate, 7c, composed of vulcanized India rubber, orof a thin plate of spring steel, the said plate ciserving as a cover toJdie valve-frame lz', as well as a spring to advance the valveimmediately after its operative lever, G, may have been forced into avertical position by eitherV end of the slot e. Each piston-head may beprovided with a series of expansive metallic packing-rings, arranged onit as represented atl lm n and o; and, with respect to the steamentrance `passages P P, disposed in the head in manner as shown in thedrawing. An auxiliary, or pump-piston head, I, is fixed to thepiston-rod E, and Works in a pump-barrel, K, whose axis is in:V

the same straight line with those of the two connected piston-heads C D.The bore of thebarrel K opens at one end into a mouth-piece, L,extending from thestuiiing-box M of the cylinder A, and being arrangedwith the said barrel in manner as shown'in the drawing. The said barrelis surmounted bya valve chest, N, which is divided into three valvechambers, grr s, and an induction chamber, t,by valveseat partitionsu uw, arranged in it, and provided with valves and valve passages, as shownat :ry z, a', and b c d' 'and e. There is an induction openin-ghf'i, toth'e chamber t, and there is also an eduction opening, g', to thechamber g; and furthermore, there are ports and passages, LZ", leadingfrom the valve chestN into the bore of the pump-barrel at ornear its'two ends, as represented. If we suppose the slide valve H of the steamVengine to be oil' the port b, so as to allow steam to flow from thechestB and act against the head D, the connected piston-heads C D, andthe piston-rod E, will be simultaneously moved` rectilinearly in thecylinder A. During this movement the lever G will be moved cn itsfulcrum by one end of the slot e, the plate h rising in the mean timeunder the pressure of the VleverG. This movement of the lever will causethe plate 7L to rise, and thevalve H tobe moved a `little more 'than'half its length of movement, the remaining portion of its movement beingproduced by the pressure of the steam in the valve chest, that is, bythe pressure of the steam o"n the llexile or elastic part or cap 7c. Sosoon as the v'alve may have been thus moved so as to cover ,the entranceof the port b, and uncover that of the port a, the steam will act on thehead C, and drive the piston in the opposite direction, the valve H inthe mean time being thrown back to its rst position. On either` port aor b being covered by the valve, the exhaust steam will flow into thevalve,'and from thence into and through the exhaust passage d, andthecylinder or the space thereof between the two connected piston-heads CD.

From the above it will be seen that the slide valve H and its operativemechanism are entirely enclosed within the cylinder and valve chest;also that the mouth-piece L not only serves to connect the steam enginewith'thc pump, and as acondenser for waste steam escaping through thestuing-box M, but it also serves as a. means of rendering unnecessary asmiling-box at that end of the pump-barrel which receives thepiston-rod.

By constructing Vthe slide-valve H in manner as described, the steam, bythe operationof the valve, will b i caused to act expansively inpropelling the piston of the engine', The valve maybe constructed andapplied ,to the lever G in 4such manner that each rectilinear movementof the valve may be produced by the lever and the slot e during themovement of the piston, in which case the' steam would not be cut oii`so asto afterward act expansively in moving the piston. Furthermore,Iwould remark that by the combination of the two sets of metallicpackings or packing-rings with the two connected piston-heads C D, andby the arrangement of the steam passages pp of the two sets of packings,in manner as described, one of the packings, while the piston is beingmoved in either direction, will be expanded, and the other willbe.collapsed that is to say, the impelling steam will expand the packingof the head against which it may bein operation, and tho packing of' theother head, or that which may be in the act of passing the exhaust steamfrom thc cylinder, will be collapsed, on account of the pressure beingequal on it in all directions, for as the exhaust steam will be on bothsides of the head. Under these circumstances the cylinder and pistonwill be relieved from friction of the packing of the advance head,l orthat in which the collapse of the packing may take place.v Thus it willbe seen that, during each stroke of the piston, it will be subjected' tothe friction of only one of the two sets of packing, but this resultwould not follow with any other' than an' expansive packing to beexpanded by the pressure of the steam.

I do not claim the application of a metallic expansive packing to apiston-head, as, this-is a very old invention;v but the employment ofthe sets ofpackigs'with the two connected heads', and with the steampassages arranged in the two heads, as set forth, is new, and productiveof a new effect, as set forth.

I claim the improved steam engine, constructed not only with the twoconnected heads C D to its piston, and with the exhaust passage oZ,extending from the steam chest laterally into the space between the saidtwo heads and out the side of the cylinder, but as provided with thelever G to extend between the two heads and into the slide valve H, suchlever being for operating with such slide valve, in manner sbstantiallyas explained.

I also claim the combination of the mouth-piece L with the forcefpumpand the lsteam engine, arranged and so as to operate substantially asspeciied.

JOHN s. BARDEN.

Witnesses.

R. H. EDDY, F. P. HALE, Jr.

